Implement correct logic for URLPatternSet set operators.

extensions/common/url_pattern_set_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "extensions/common/url_pattern_set.h"
 
 #include "base/values.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "url/gurl.h"
 
 namespace extensions {
 
 namespace {
 
 void AddPattern(URLPatternSet* set, const std::string& pattern) {
   int schemes = URLPattern::SCHEME_ALL;
   set->AddPattern(URLPattern(schemes, pattern));
 }
 
+void AddMatchAllURLsPattern(URLPatternSet* set) {
+  URLPattern pattern;
+  pattern.SetMatchAllURLs(true);
+  set->AddPattern(pattern);
+}
+
 URLPatternSet Patterns(const std::string& pattern) {
   URLPatternSet set;
   AddPattern(&set, pattern);
   return set;
 }
 
 URLPatternSet Patterns(const std::string& pattern1,
                        const std::string& pattern2) {
   URLPatternSet set;
   AddPattern(&set, pattern1);
@@ skipping 356 matching lines @@
     AddPattern(&expected, yahoo_a);
     AddPattern(&expected, yahoo_b);
     AddPattern(&expected, yahoo_c);
     AddPattern(&expected, reddit_a);
     AddPattern(&expected, reddit_b);
     AddPattern(&expected, reddit_c);
     EXPECT_EQ(expected, result);
   }
 }
 
+TEST(URLPatternSetTest, SubsetSpecialCases) {
+  URLPatternSet empty;
+  URLPatternSet all_urls;
+  AddMatchAllURLsPattern(&all_urls);

[not at google - send to devlin, 2014/02/27 21:10:46]

presumably these sets are copyable. so you could have
URLPatternSet all_urls = GetAllURLsPattern();
then change AddMatchAllURLsPattern.

+  URLPatternSet specific;
+  AddPattern(&specific, "http://www.google.com/*");
+  AddPattern(&specific, "http://www.yahoo.com/*");
+

[not at google - send to devlin, 2014/02/27 21:10:46]

there are some other cases here that it might be good to test, like overlapping
sets, having "*://www.google.com" and "http://*.google.com" in different/same
sets, etc. you might consider breaking up into separate test cases if that makes
it any easier, not sure about that.

+  {
+    URLPatternSet result;
+    result.AddPatterns(specific);
+    EXPECT_EQ(specific, result);
+    result.AddPatterns(all_urls);
+    EXPECT_EQ(all_urls, result);
+  }
+  {
+    URLPatternSet result;
+    result.AddPatterns(all_urls);
+    EXPECT_EQ(all_urls, result);
+    result.AddPatterns(specific);
+    EXPECT_EQ(all_urls, result);
+  }
+  {
+    URLPatternSet result;
+    URLPatternSet::CreateUnion(all_urls, specific, &result);
+    EXPECT_EQ(all_urls, result);
+  }
+  {
+    URLPatternSet result;
+    URLPatternSet::CreateUnion(specific, all_urls, &result);
+    EXPECT_EQ(all_urls, result);
+  }
+  {
+    URLPatternSet result;
+    URLPatternSet::CreateIntersection(all_urls, specific, &result);
+    EXPECT_EQ(specific, result);
+  }
+  {
+    URLPatternSet result;
+    URLPatternSet::CreateIntersection(specific, all_urls, &result);
+    EXPECT_EQ(specific, result);
+  }
+  {
+    URLPatternSet result;
+    URLPatternSet::CreateDifference(all_urls, specific, &result);
+    EXPECT_EQ(all_urls, result);
+  }
+  {
+    URLPatternSet result;
+    URLPatternSet::CreateDifference(specific, all_urls, &result);
+    EXPECT_EQ(empty, result);
+  }
+}
+
 }  // namespace extensions